Mimulus aurantiacus Curtis var. aurantiacus, BUSH MONKEYFLOWER, STICKY MONKEYFLOWER. Subshrub to shrub, drought-deciduous during late summer, with opposite branches and short unexpanded axillary shoots having leaves clustered at nodes, in range 30−150 cm tall; shoots pubescent to pilose with some nonglandular hairs but mostly glandular hairs, sticky-resinous on new growth, pleasantly aromatic. Stems: cylindric, on vigorous shoots internodes 50−100 mm long, velveteen glandular-hairy, the hairs mostly short with scattered long ones; pith solid, white; young woody stems having flaking tannish bark with brown epidermis. Leaves: opposite decussate, simple, short- petiolate or sessile with pair fused narrowly forming hairy ledges across node, (young leaves sessile on unexpanded axillary shoots), without stipules; petiole < 4 mm long; blade elliptic, narrowly elliptic, or lanceolate (obovate), appearing linear when margins inrolled, (20−)25−105 × (3−)7−30 mm, flat to inrolled under (revolute), tapered at base and grading into short petiole, entire or serrate to dentate on margins, acute at tip, pinnately veined with principal veins slightly sunken on upper surface and raised on lower surface, initially very glandular, upper surface becoming glabrescent, lower surface retaining short and long nonglandular and glandular hairs. Inflorescence: leafy raceme, terminal, of showy, axillary flowers paired and spreading at nodes, glandular-hairy; bract subtending pedicel leaflike; pedicel generally short, 2−16 mm long. Flower: bisexual, bilateral, 25–35 mm across; calyx 5-lobed, 18−35 mm long, green, distinctly 5-pleated, glandular-pubescent and glandular–pilose to glandular-tomentose and very resinous; tube narrowly funnel- shaped, to 21 mm long, not inflated, internally finely puberulent; lobes unequal, acute to acuminate, upper lobe the longest, 4−13 mm long, lower lobes the shortest, 3−5.7 mm long, generally folded upward lengthwise with halves sticking together, green (not reddish at tip), << tube; corolla 2-lipped, 5-lobed, in range (25–)35−55 mm long, typically orange-yellow and sometimes with white markings in throat, occasionally pale orange, light yellow, buff, nearly white, red-orange or red, glabrous; tube ± included in calyx tube, 15–20 × 1.5–3 mm; throat 20–24 mm long, expanding from above calyx lobes to 6–9 mm wide at orifice, generally exceeding calyx by > 10 mm; upper lip 2-lobed, with sinus 8–13 mm deep between the lobes, lobes usually toothed, sometimes with a smaller sublobe on outer edge; lower lip, 3-lobed, with sinuses between central and lateral lobes 7–9 mm deep, central lobe oblong or wedge-shaped, ca. 10 mm wide, slightly narrower at base, 2- toothed at tip, lateral lobes oblong, ca. 8 mm wide, irregular 3 lobed or toothed at tip; stamens 4, lacking staminode, fused to corolla at top of tube, included, pressed to upper side of throat, slightly dimorphic; filaments ± straight, 15–18 mm long and ca. 0.5 mm thick at base (lower stamens) and 9–10 mm long and ca. 0.4 mm thick at base (upper stamens), orange-yellow, swollen below, glabrous; anthers dithecal with divergent sacs, M-shaped, ca. 2.3 mm long (upper stamens) and ca. 2 mm long (lower stamens), red- orange (variable in different color morphs) , longitudinally dehiscent; pollen light orange- yellow or light yellow; pistil 1, ca. 40 mm long; ovary superior, compressed narrowly conic to ± miter-shaped, at anthesis ca. 5 × 2 mm, ridged on lateral edges, glabrous and nonglandular, 2-chambered, each chamber with many ovules attached to center; style white, glandular-puberulent most of length, becoming glabrate above ovary, positioned along ceiling of throat; stigmas 2, flat and widely spreading but becoming appressed rapidly when touched, spade-shaped to rhombic, 2.2–3 mm long and wide, white, conspicuously papillate-pilose. Fruit: capsule, loculicidal, 2-valved, many-seeded, narrowly ovoid to narrowly fusiform, 22−25 × 3.5 × 2.5 mm, brown, ridged along dehiscence lines, valves veiny, ± glutinous; with persistent corolla tube concealing fruit. Seed: compressed-ellipsoid, ca. 0.8 mm long, brown, with nipple on each end. Late January−early August.

Native. Shrub (subshrub) common throughout the range in coastal sage scrub and chaparral. Mimulus aurantiacus var. aurantiacus formerly was treated as M. longiflorus or as a species in Diplacus, and appears to be the only woody species in range. This species is resinous with glandular hairs on shoots and calyx. Color of flowers varies from site to site, sometimes nearly uniform and sometimes locally variable; typical corolla color is yellow-orange to pale orange, but some sites have mostly pale color, more orange-yellow, or rarely red and red-orange. White mutants have been observed in range. Red-flowered populations, of which there are several in range, have been treated as M. aurantiacus var. puniceus (Nutt.) D. M. Thomps., which is more common south of our range, but for our plants the distinction seems trivial and so has not been recognized. The most accessible red-flowered population is above Chatsworth Park South (SH), growing around several large sandstone boulders surrounded by individuals with typical orange flowers. B. A. Prigge & A. C. Gibson